JPH09316312A - Polycarbonate resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polycarbonate resin composition reduced in pyrolytic deterioration during molding, etc., and having excellent thermal stability by incorporating a metal salt and an epoxidized vegetable oil into a polycarbonate. SOLUTION: The composition comprises 100 pts.wt. polycarbonate (A), 0.01-5 pts.wt. metal salt (B), and 0.01-0.5 pts.wt. epoxidized vegetable oil (C). If the amount of the salt (B) exceeds 5 pts.wt., the mol.wt. of the polycarbonate resin is reduced. If the amount thereof is smaller than 0.01 pt.wt., the effect of a pigment, etc., is reduced. Even if the amount of the oil (C) exceeds 0.5 pts.wt., the effect of pyrolysis inhibition is not enhanced any more. If the amount thereof is smaller than 0.01 pt.wt., the effect of pyrolysis inhibition is insufficient. The addition of the oil (C) serves to reduce the amount of phenols which generate through decomposition and dissolve away to about one-tenth that in the composition not containing the oil (C). This composition is especially suitable for use as a molding material for food containers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polycarbonate resin composition using a metal salt as a pigment or the like, which is excellent in thermal stability by suppressing thermal decomposition deterioration during molding.

[0002]

2. Description of the Related Art Polycarbonate resin is blended with a white pigment, a metal-based lubricant, and a metal salt such as titanium dioxide, zinc oxide, or lead sulfate as a filler to prepare a resin composition, or to prepare the resin composition. It is known that the thermal decomposition degradation of the polycarbonate resin is accelerated by these metal salts during thermoforming such as injection molding.

When such decomposition progresses, the molecular weight decreases and a monomer such as bisphenol A, which is a polymerized constitutional unit, is produced, impairing the excellent mechanical properties and appearance of the polycarbonate resin molded article, and particularly in food containers. There is a risk of increasing the amount of monomer elution in the elution test of the food container safety standard, and there is a great need and urgent need for technological development to suppress the decomposition.

As a solution to such a problem, a method of adding a special organosiloxane has been proposed (Japanese Patent Laid-Open No. 6-200140), but a method of bleeding out organosiloxane on the surface of the obtained molded article is proposed. As a result, the transfer film is not sufficient, such as peeling of the transfer film from the molded product, causing a defect in transferability.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a resin composition containing a polycarbonate resin and various fillers containing a metal salt such as titanium dioxide, which is excellent in thermal stability with little thermal decomposition deterioration during molding. An object is to provide a polycarbonate resin composition.

[0006]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that by adding a small amount of epoxidized vegetable oil, the heat of a polycarbonate resin composition containing a metal salt such as titanium dioxide can be improved. The inventors have found that it has an effect of suppressing decomposition and have completed the present invention. That is,
The present invention provides a polycarbonate resin composition comprising 100 parts by weight of (A) polycarbonate and 0.01 to 5 parts by weight of (B) metal salt and 0.01 to 0.5 parts by weight of (C) epoxidized vegetable oil. It is a summary.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. Each component constituting the polycarbonate resin composition of the present invention will be described in order. Polycarbonate of component (A) The polycarbonate of component (A) can be produced by a conventional production method, that is, by reacting a dihydric phenol with a polycarbonate precursor such as phosgene or a carbonate compound. . Specifically, for example, in a solvent such as methylene chloride, in the presence of a known acid acceptor and a molecular weight modifier, a branching agent is further added, if necessary, to prepare a dihydric phenol and a carbonate precursor such as phosgene. It is produced by a reaction or by a transesterification reaction between a dihydric phenol and a carbonate precursor such as diphenyl carbonate.

There are various dihydric phenols, and in particular 2,2-bis (4-hydroxyphenyl).
Propane (commonly known as bisphenol A) is preferred. Examples of bisphenols other than bisphenol A include bis (4-hydroxyphenyl) methane; 1,1-
Bis (4-hydroxyphenyl) ethane; 2,2-bis (4-hydroxyphenyl) butane; 2,2-bis (4
-Hydroxyphenyl) octane; 2,2-bis (4-
Hydroxyphenyl) phenylmethane; 2,2-bis (4-hydroxy-1-methylphenyl) propane; bis (4-hydroxyphenyl) naphthylmethane; 1,1
-Bis (4-hydroxy-t-butylphenyl) propane; 2,2-bis (4-hydroxy-3-bromophenyl) propane; 2,2-bis (4-hydroxy-3,5
-Tetramethylphenyl) propane; 2,2-bis (4
-Hydroxy-3-chlorophenyl) propane; 2,2
-Bis (4-hydroxy-3,5-tetrachlorophenyl) propane; 2,2-bis (4-hydroxy-3,5
-Bis (hydroxyaryl) alkanes such as tetrabromophenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclopentane; 1,1-bis (4-hydroxyphenyl) cyclohexane; 1,1-bis (4 −
Bis (hydroxyaryl) cycloalkanes such as (hydroxyphenyl) -3,5,5-trimethylcyclohexane, 4,4′-dihydroxyphenyl ether;
Dihydroxyaryl ethers such as 4'-dihydroxy-3,3'-dimethylphenyl ether; 4,4'-
Dihydroxydiphenyl sulfide; dihydroxydiaryl sulfides such as 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide; and 4,4'-dihydroxydiphenyl sulphoxide; 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulphoxide Dihydroxydiarylsulfoxides; 4,4'-dihydroxydiphenylsulfone; dihydroxydiarylsulfones such as 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone; dihydroxydiphenyls such as 4,4'-dihydroxydiphenyl And the like. These dihydric phenols may be used alone or in combination of two or more.

Examples of the carbonic acid ester compound include diaryl carbonates such as diphenyl carbonate, dialkyl carbonates such as dimethyl carbonate and diethyl carbo. As the molecular weight modifier, those usually used for polymerization of polycarbonate may be used, and various kinds may be used. Specifically, as the monohydric phenol, for example, phenol, on-butylphenol, mn-butylphenol, pn-
Butylphenol, o-isobutylphenol, m-isobutylphenol, p-isobutylphenol, o-
t-butylphenol, mt-butylphenol, p
-T-butylphenol, on-pentylphenol, mn-pentylphenol, pn-pentylphenol, on-hexylphenol, mn-hexylphenol, pn-hexylphenol, pt
-Octylphenol, o-cyclohexylphenol, m-cyclohexylphenol, p-cyclohexylphenol, o-phenylphenol, m-phenylphenol, p-phenylphenol, on-nonylphenol, m-nonylphenol, pn-nonylphenol, o -Cumylphenol, m-cumylphenol, p-cumylphenol, o-naphthylphenol,
m-naphthylphenol, p-naphthylphenol;
2,5-di-t-butylphenol; 2,4-di-t-butylphenol
Butylphenol; 3,5-di-t-butylphenol; 2,5-dicumylphenol; 3,5-dicumylphenol; p-cresol, bromophenol, tribromophenol and the like. Among these monohydric phenols, pt-butylphenol, p-cumylphenol, pt-octylphenol, phenol and the like are preferably used.

Other branching agents include, for example, 1,1,
1-tris (4-hydroxyphenyl) ethane; α,
α ′, α ″ -tris (4-hydroxyphenyl) -1,
3,5-triisopropylbenzene; 1- [α-methyl-α- (4′-hydroxyphenyl) ethyl] -4-
[Α ′, α′-bis (4 ″ -hydroxyphenyl) ethyl] benzene; compounds having three or more functional groups such as phloroglysin, trimellitic acid, and isatin bis (o-cresol) can also be used.

The polycarbonate used in the present invention usually has a viscosity average molecular weight of 10,000 to 40,000.
0, preferably 12,000 to 35,000.
0, more preferably 15,000 to 30,000. If it is less than 10,000, the impact resistance is poor, and 4
If it is more than 000, molding is difficult. (B) Metal salt As the metal salt of the component (B), stannic oxide, lead sulfate,
Lead chromate, lead trioxide, lead monoxide, zinc sulfide, zinc oxide, zinc carbonate, cadmium sulfate, cadmium sulfide, cadmium oxide, cadmium carbonate, aluminum oxide, cobalt oxide, barium sulfate, titanium dioxide, copper oxide, dioxide Examples thereof include manganese, ferric oxide, chromic oxide, cadmium selenide and the like. These metal salts may be used alone or in combination of two or more, and most of them are used as pigments, lubricants and inorganic fillers, and among them, titanium dioxide is most commonly used as a white pigment.

Further, it is known that these metal salts accelerate the thermal decomposition of the polycarbonate resin, and therefore, these metal salts are preliminarily subjected to a surface coating treatment such as silica, hydrated aluminum or silicon treatment. May be used. Among them, those surface-treated with silica / alumina and dimethyl silicon have a great effect of suppressing decomposition and can be preferably used.

(C) Epoxidized vegetable oil The epoxidized vegetable oil as the component (C) may be one produced by a known production method. Generally, vegetable oils and fats are subjected to carboxylic acid and peroxidation in the presence of an acidic catalyst. It is epoxidized using an oxidizing agent composed of hydrogen. Specifically, soybean oil, cottonseed oil, rice bran oil and the like are targeted as vegetable oils and fats, but soybean oil is most often used. As the acidic catalyst, those generally used in the in-situ method, particularly sulfuric acid, are preferably used. Formic acid, acetic acid, and propionic acid can be used as the carboxylic acid, and 25 to 70% concentration of hydrogen peroxide can be used.
A method for producing these epoxidized vegetable oils is disclosed in, for example, Japanese Patent Laid-Open No.
It is disclosed in Japanese Patent Publication No. 107652.

The resin composition of the present invention contains 0.01 to 5 parts by weight of the (B) metal salt in 100 parts by weight of the (A) polycarbonate resin.
It is a polycarbonate resin composition which mix | blends 0.01 to 0.5 weight part of (C) epoxidized vegetable oils with 1 weight part.
The amount of the metal salt (B) is usually 0.01 to 5 parts by weight, preferably 0.05 to 4 parts by weight, more preferably 0.1 to 4 parts by weight.
3 parts by weight. When it exceeds 5 parts by weight, the molecular weight of the polycarbonate resin decreases, and when it is less than 0.01 parts by weight, the effect of the pigment and the like is small.

The epoxidized vegetable oil (C) is usually 0.01
~ 0.5 parts by weight, but preferably 0.02 to 0.3
Parts by weight, more preferably 0.05 to 0.1 parts by weight. If it exceeds 0.5 parts by weight, the effect of suppressing thermal decomposition does not improve, and if it is less than 0.01 part by weight, the effect of suppressing thermal decomposition becomes insufficient. The method of blending the resin composition of the present invention,
The above components (A), (B) and (C) may be blended with each other, or the metal salt of the component (B) treated with the epoxidized vegetable oil of the component (C) may be used.

The resin composition of the present invention comprises the above-mentioned components (A),
In addition to (B) and (C), various inorganic fillers, additives, other synthetic resins and the like can be blended, if necessary, within a range that does not impair the object of the present invention. First, the mechanical strength of the polycarbonate resin composition, the inorganic filler to be blended for the purpose of increasing the durability, for example, glass fiber, carbon fiber, gas beads, glass flakes, carbon flakes, carbon black, calcium sulfate, Calcium carbonate, calcium silicate, titanium oxide,
Alumina, silica, asbestos, talc, clay, mica, quartz powder and the like can be mentioned. Examples of the additive include antioxidants such as hindered phenol-based, phosphorus-based (phosphite-based, phosphate-based), and amine-based antioxidants, such as benzotriazole-based and benzophenone-based ultraviolet absorbers, such as fats External lubricants such as aromatic carboxylic acid ester type, paraffin type, silicone oil, polyethylene wax and the like, common flame retardants, release agents, antistatic agents, coloring agents and the like.

Other synthetic resins include polyethylene, polypropylene, polystyrene, AS resin and ABS.
Examples of the resin include resins and polymethylmethacrylate. The compounding and kneading are methods usually used,
For example, it can be performed by a method using a ribbon blender, a Henschel mixer, a Banbury mixer, a drum tumbler, a single screw extruder, a twin screw extruder, a co-kneader, a multi-screw extruder, or the like. The heating temperature at the time of kneading is usually selected in the range of 240 to 300 ° C.

The polycarbonate resin composition thus obtained can be applied by various known molding methods such as injection molding, blow molding, extrusion molding, compression molding, calender molding, rotational molding, electrical and electronic equipment, Daily necessities,
It can be used to manufacture molded products such as toys, food containers, and packaging materials. Above all, in a food container using titanium dioxide as a white pigment, the amount of monomer elution in the food container elution test is suppressed, and it can be suitably used.

[0019]

EXAMPLES The present invention will be described in more detail with reference to Production Examples, Examples and Comparative Examples. Example 1 As a polycarbonate resin, 100 parts by weight of Teflon FN2200 (Mv: 21500) manufactured by Idemitsu Petrochemical Co., Ltd., and as a white pigment, titanium dioxide [CR-60 manufactured by Ishihara Sangyo Co., Ltd. (titanium dioxide was surface-treated with 3% alumina). , CR-63 (titanium dioxide surface-treated with 1% silica / alumina and 0.5% dimethyl silicone)] 1.5 parts by weight, as epoxidized soybean oil, Adeka Stab O- manufactured by Asahi Denka Kogyo Co., Ltd. Using 0.08 part by weight of 130P, and as an antioxidant (a)
0.08 parts by weight of tris (nonylphenyl) phosphite was blended and extruded into pellets at 280 ° C. The blending ratio of each component is shown in Table 1.

[0020]

[Table 1]

The viscosity average molecular weight Mv of the polycarbonate resin was calculated by measuring the intrinsic viscosity [η] of the methylene chloride solution at 20 ° C. with an Ubbelohde type viscosity tube and calculating the following relational expression. [Η] = 1.23 × 10 ⁻⁵ Mv ^0.83 Bisphenol A (BPA) and p − in the obtained pellets
The amount of tert-butylphenol (PTBP) is shown in Table 2.

Method for measuring the amount of BPA and PTBP 2.0 g of pellets are dissolved in 50 cc of dichloromethane and 250 cc of acetone is added to reprecipitate the polymer. The polymer is filtered off, 50 cc of acetonitrile is added to the resulting acetone solution and heated to evaporate the acetone. Water is added, and the volume is adjusted to 50 cc with a solution of acetonitrile: water = 1: 1. It was measured by liquid chromatography of the obtained solution.

[0023]

[Table 2]

Example 2 In Example 1, except that the amount of titanium dioxide added was 3.0 parts by weight and tris (2,4-di-tert-butylphenyl) phosphite (b) was used as an antioxidant. Was carried out similarly. The blending ratio of each component is shown in Table 1. Table 2 shows the amounts of bisphenol A (BPA) and p-tert-butylphenol (PTBP) in the obtained pellets.

Example 3 In Example 1, the amount of titanium dioxide added was 0.75 parts by weight, and (c) tetrakis (2,4-di-te) was used as an antioxidant.
rt-Butylphenyl) 4,4′-bisphenylenediphosphite was used in the same manner as above. The blending ratio of each component is shown in Table 1. Bisphenol A in the obtained pellets
The amounts of (BPA) and p-tert-butylphenol (PTBP) are shown in Table 2.

Examples 4 to 6 and Comparative Examples 1 to 4 The components and their blending ratios are shown in Table 1 and the same procedure as in Example 1 was carried out. Bisphenol A (BPA) and p-tert-butylphenol (PTB in the obtained pellets
The amount of P) is shown in Table 2.

[0027]

EFFECTS OF THE INVENTION According to the present invention, the addition of epoxidized vegetable oil reduces the elution amount of decomposed phenols to about 1/10 of that of the additive-free product. In particular, the resin composition in which the elution amount is suppressed is suitable for use as a molding material for food containers.

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Claims (1)

[Claims] 1. A polycarbonate resin composition comprising 100 parts by weight of (A) polycarbonate and 0.01 to 5 parts by weight of (B) metal salt and 0.01 to 0.5 parts by weight of (C) epoxidized vegetable oil. .